Replace roller rubber on HP 9825 tape drive

[Dwight K. Elvey]

>From: "Joe R." <rigdonj at cfl.rr.com>
>
>At 11:59 AM 7/7/05 -0700, Dwight wrote:
>>>From: "Joe R." <rigdonj at cfl.rr.com>
>>>
>>>At 12:10 AM 7/7/05 +0100, you wrote:
>>>>> 
>>>>> Well, I finally got around to attempting to re-spool this stupidly
>>>>> designed tape.
>>>>
>>>>It's actually avery ingenious design (it's the same design, basically, as 
>>>>QIC tape cartridges). Remember you want a constant tape speed past the 
>>>>head. By driving the outside of the tape spools at a constant speed 
>>>>(that's what the belt and drive puck do), rather than turning the spools 
>>>>themselves by their axles, that's exactly what you get. It avoids the 
>>>>capstan, pinch roller, slipping clutches, etc, used in audio tape and 
>>>>cassette recorders.
>>>
>>>   The really ingenous part is that the belt attempts to rotate the take up
>>>spool about 10% faster then the other spool. That's what tightens up the
>>>tape if it ever gets slack.
>>>
>>>
>>>>
>>>>> 
>>>>> Your description sounds like a different tape than what I was dealing
>>>>> with.  The tape did not come off of either spool but was instead attached
>>>>> onto both spools.
>
>   That really wouldn't make any difference as long as the drive stops when
>it sees the BOT/EOT hole and doesn't run the tape off the spool.
>
>>>>
>>>>THere were several designs, sure...
>>>>
>>>>> 
>>>>> At any rate, the stupid tensioning belt (whatever its called) broke on
>me.
>>>>> Oh well, fuck that tape.  I'll try to read it anyway (is the tensioning
>>>>> belt necessary?)  I also noticed numerous spots on the the tape where the
>>>>
>>>>Of course the belt is necessary. It's how the tape is driven. You can 
>>>>borrow one from another tape cartridge.
>>>
>>>   Good luck! I could never replace a belt and make it work :=/
>>
>>Hi Joe
>> I have but I'll admit it was not easy. It is real easy to get
>>the tape mangled. I've also repaired the roller at the corners
>>on one.
>> I don't know how it is done at the factory but they must have
>>a special jig to get it all done right.
>
>  Oh, I've gotten them back together (but you need about six hands to do
>it)! But even though they're back together exactly like an original they
>would never tighten up the slack. They'd run (till the slack got caught and
>wrapped under the tape on the take-up spool) but simply never take the
>slack out of the tape. Perhaps if I could run them at a slow speed the
>slack would eventually work it self out without getting caught and they'd
>be ok.  But to tell the truth I've never had much luck with tape drives and
>I dispise the things!
>
>   Joe

Hi Joe
 I had a trick to get the slack out but it was a long
time ago and I've forgotten. I think I just ran is slowly
by hand and it took the slack up but I just don't recall.
Getting all the pins lined up at the same time was more
of an issue. Like you said, it takes six or so hands.
 I was wondering if one completely unwound it onto
a single spool that one could get it to take up the slack
by threading it through on its own? It seems like they
must have done something like this when they assembled
them the first time.
 The design is such that it always pulls slightly more
on the takeup reel. It isn't much but enough to take
up the slack if it is only a little.
Dwight